Liquid Crystal Interface Control and Phenomena

Case Western Reserve University, Cleveland OH

Investigators

Abstract

This award to Case Western Reserve University by the Solid State Materials Chemistry program in the Division of Materials Research is to enhance our understanding about the nature of interaction between surfaces and liquid crystal, especially in the realm of controlled polar tilt. The main goal of the project includes novel approaches to alignment using ink-jet technology, to quasiperiodic dielectric lasers based on liquid crystals, and to surface chirality-induced polarization phenomena. Advances in these areas are expected to transform our conceptions about, and methodology toward, liquid crystal orientation control and applications. Additionally, the proposed work seeks to achieve significantly improved control and much deeper understandings of anchoring well beyond the harmonic approximation and of reverse tilt domains and associated topological defects. In this light, the proposed work has several objectives interconnected by the common theme of surface manipulation. As part of this project, two different aligning polyimides will be used to control pretilt angle of the liquid crystal on length scales as small as a few micrometers. These studies are expected to develop a novel electrically-switchable, polarization-independent blazed grating. The proposed studies with quasiperiodic dielectric structures via surface orientation control are expected to serve as photonic band gap devices, and may be used as highly tunable mirrorless lasers. The scientific broad impact of the proposal could be very strong in understanding the basic science behind the interactions of liquid crystals with alignment layers and the basic soft condensed matter physics about these alignments and interactions. The properties of new gratings that are planned would have interesting applications as lasing media and new devices such as laser beam steering and adaptive optics. The proposed teaching, training and outreach activities of students from High School to Postdoctoral levels would have a significant impact in developing a strong pool of future scientists. As part of this research project, new graduate and undergraduate courses such as ?Optics of Complex Fluids? and ?The Physics of Liquid Crystals? will be further developed and expanded, and will be incorporated in to Case Western University curriculum.